warning light JEEP WRANGLER 2012 JK / 3.G Service Manual

WARNING!
Many factors, such as vehicle loading, road conditions
and driving conditions, influence the chance that
wheel lift or rollover may occur. Electronic Roll Miti-
gation (ERM) cannot prevent all wheel lift or rollovers,
especially those that involve leaving the roadway or
striking objects or other vehicles. The capabilities of an
ERM-equipped vehicle must never be exploited in a
reckless or dangerous manner which could jeopardize
the user’s safety or the safety of others.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. The ESC
corrects for over/under steering of the vehicle by apply-
ing the brake of the appropriate wheel to assist in
counteracting the over/under steer condition. Engine
power may also be reduced to help the vehicle maintain
the desired path.ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESC applies the brake of the appro-
priate wheel to assist in counteracting the oversteer or
understeer condition.
•Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
•Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” (lo-
cated in the instrument cluster), starts to flash as soon as
the tires lose traction and the ESC system becomes active.
The “ESC Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC Activation/
Malfunction Indicator Light” begins to flash during ac-
celeration, ease up on the accelerator and apply as little
throttle as possible. Be sure to adapt your speed and
driving to the prevailing road conditions.5
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WARNING!
With the ESC switched off, the enhanced vehicle
stability offered by ESC and ERM are unavailable. In
an emergency evasive maneuver, the ESC and ERM
systems will not engage to assist in maintaining
stability. The “Full Off” ESC mode is intended for
off-road use only.
4L Range (4WD Models)
ESC Off
This is the normal operating mode for ESC in 4L range.
Whenever the vehicle is started in 4L range, or the
transfer case (if equipped) is shifted from 4H range or
NEUTRAL to 4L range, the ESC system will be in this
mode. In 4L range, ESC and TCS, except for the “limitedslip” feature described in the TCS section, are turned off
until the vehicle reaches a speed of 40 mph (64 km/h). At
40 mph (64 km/h), the normal ESC stability function
returns but TCS remains off. When the vehicle speed
drops below 35 mph (56 km/h), the ESC system shuts off.
The ESC is off at low vehicle speeds in 4L range so that it
will not interfere with off-road driving, but the ESC
function returns to provide the stability feature at speeds
above 40 mph (64 km/h). The “ESC Activation/
Malfunction Indicator Light” will always be illuminated
in 4L range when ESC is off.
NOTE:
The “ESC OFF” message will display and the
audible chime will sound when the shift lever is placed in
the PARK position from any position other than PARK,
and then moved out of the PARK position. This will
occur even if the message was previously cleared.
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WARNING!
With the ESC switched off, the enhanced vehicle
stability offered by ESC and ERM are unavailable. In
an emergency evasive maneuver, the ESC and ERM
systems will not engage to assist in maintaining
stability. The “Full Off” mode is intended for off-
road use only.
ESC Activation/Malfunction Indicator Light And
ESC OFF Indicator Light
The “ESC Activation/Malfunction Indicator
Light” in the instrument cluster will come on
when the ignition switch is turned to the ON
position. It should go out with the engine
running. If the “ESC Activation/Malfunction Indicator
Light” comes on continuously with the engine running, a
malfunction has been detected in the ESC system. If this
light remains on after several ignition cycles, and the vehicle has been driven several miles (kilometers) at
speeds greater than 30 mph (48 km/h), see your autho-
rized dealer as soon as possible to have the problem
diagnosed and corrected.
The “ESC Activation/Malfunction Indicator Light” (lo-
cated in the instrument cluster) starts to flash as soon as
the tires lose traction and the ESC system becomes active.
The “ESC Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC Activation/
Malfunction Indicator Light” begins to flash during ac-
celeration, ease up on the accelerator and apply as little
throttle as possible. Be sure to adapt your speed and
driving to the prevailing road conditions.
NOTE:
•The “ESC Activation/Malfunction Indicator Light”
and the “ESC OFF Indicator Light” come on momen-
tarily each time the ignition switch is turned ON.
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•Each time the ignition is turned ON, the ESC system
will be ON even if it was turned off previously.
•The ESC system will make buzzing or clicking sounds
when it is active. This is normal; the sounds will stop
when ESC becomes inactive following the maneuver
that caused the ESC activation.The “ESC OFF Indicator Light” indicates the
Electronic Stability Control (ESC) is off.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an exces-
sively swaying trailer and will take the appropriate
actions to attempt to stop the sway. The system may
reduce engine power and apply the brake of the appro-
priate wheel(s) to counteract the sway of the trailer. TSC
will become active automatically once an excessively swaying trailer is recognized. No driver action is re-
quired. Note that TSC cannot stop all trailers from
swaying. Always use caution when towing a trailer and
follow the tongue weight recommendations. Refer to
“Trailer Towing” in “Starting and Operating” for further
information. When TSC is functioning, the “ESC
Activation/Malfunction Indicator Light” will flash, the
engine power may be reduced and you may feel the
brakes being applied to individual wheels to attempt to
stop the trailer from swaying. TSC is disabled when the
ESP system is in the “Partial Off” or “Full Off” modes.WARNING!
If TSC activates while driving, slow the vehicle
down, stop at the nearest safe location, and adjust the
trailer load to eliminate trailer sway.
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Life Of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
•Driving style
•Tire pressure
•Distance driven
WARNING!
Tires and the spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have a collision resulting
in serious injury or death.
Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the “Tire and Loading Infor-
mation” placard for the size designation of your tire. The
Load Index and Speed Symbol for your tire will be found
on the original equipment tire sidewall. See the Tire
Sizing Chart example found in the Tire Safety Informa-
tion section of this manual for more information relating
to the Load Index and Speed Symbol of a tire.
It is recommended to replace the two front tires or two
rear tires as a pair. Replacing just one tire can seriously
affect your vehicle’s handling. If you ever replace a
wheel, make sure that the wheel’s specifications match
those of the original wheels.
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The TPMS will warn the driver of a low tire pressure if
the tire pressure falls below the low pressure warning
threshold for any reason, including low temperature
effects, or natural pressure loss through the tire.
The TPMS will continue to warn the driver of low tire
pressure as long as the condition exists, and will not turn
off until the tire pressure is at or above recommended
cold placard pressure. Once the “Tire Pressure Monitor-
ing Telltale Light” has been illuminated, the tire pressure
must be increased to the recommended cold placard
pressure in order for the “Tire Pressure Monitoring
Telltale Light” to be turned OFF. The system will auto-
matically update and the “Tire Pressure Monitoring
Telltale Light” will extinguish once the updated tire
pressures have been received. The vehicle may need to be
driven for up to 20 minutes above 15 mph (24 km/h) to
receive this information.For example, your vehicle may have a recommended
cold (parked for more than three hours) air pressure of
35 psi (241 kPa). If the ambient temperature is 68°F (20°C)
and the measured tire pressure is 30 psi (207 kPa), a
temperature drop to 20°F (-7°C) will decrease the tire
pressure to approximately 26 psi (179 kPa). This tire
pressure is sufficiently low enough to turn ON the “Tire
Pressure Monitoring Telltale Light.” Driving the vehicle
may cause the tire pressure to rise to approximately
30 psi (207 kPa), but the “Tire Pressure Monitoring
Telltale Light” will still be ON. In this situation, the “Tire
Pressure Monitoring Telltale Light” will turn OFF only
after the tires have been inflated to the vehicle’s recom-
mended cold placard pressure value.
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CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. The TPMS pressures
have been established for the tire size equipped
on your vehicle. Undesirable system operation or
sensor damage may result when using replace-
ment equipment that is not of the same size, type,
and/or style. Aftermarket wheels can cause sensor
damage. Do not use aftermarket tire sealants or
balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result.
•After inspecting or adjusting the tire pressure,
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the valve
stem, which could damage the Tire Pressure Moni-
toring Sensor.NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, nor to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
•The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure, even if under-inflation has not
reached the level to trigger illumination of the “Tire
Pressure Monitoring Telltale Light.”
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extinguish once the updated tire pressures have been
received. The vehicle may need to be driven for up to
20 minutes above 15 mph (24 km/h) to receive this
information.
The “Tire Pressure Monitoring Telltale Light” will flash
on and off for 75 seconds, and will remain on solid when
a system fault is detected. The system fault will also
sound a chime. If the ignition key is cycled, this sequence
will repeat, providing the system fault still exists. A
system fault can occur by any of the following scenarios:
1. Jamming due to electronic devices or driving next to
facilities emitting the same Radio Frequencies as the TPM
sensors.
2. Installing some form of aftermarket window tinting
that affects radio wave signals.
3. Lots of snow or ice around the wheels or wheel
housings.4. Using tire chains on the vehicle.
5. Using wheels/tires not equipped with TPM sensors.
NOTE:
•If your vehicle is equipped with a matching full-size
spare wheel and tire assembly, it has a tire pressure
monitoring sensor, and can be monitored by the Tire
Pressure Monitoring System (TPMS). In the event that
the matching full-size spare tire is swapped with a low
pressure road tire, the next ignition key cycle will still
show the “Tire Pressure Monitoring Telltale Light” to
be ON, and a chime to sound. Driving the vehicle for
up to 20 minutes above 15 mph (24 km/h) will turn
OFF the “Tire Pressure Monitoring Telltale Light” as
long as none of the road tires are below the low
pressure warning threshold.
•If your vehicle is not equipped with a matching
full-size spare wheel and tire assembly, it does not
have a tire pressure monitoring sensor in the spare tire.
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The TPMS will not be able to monitor the tire pressure.
If you install the spare tire in place of a road tire that
has a pressure below the low-pressure warning limit,
upon the next ignition key cycle, a chime will sound
and the “Tire Pressure Monitoring Telltale Light” will
turn ON. After driving the vehicle for up to 20 minutes
above 15 mph (24 km/h), the “Tire Pressure Monitor-
ing Telltale Light” will flash on and off for 75 seconds
and then remain on solid. For each subsequent ignition
key cycle, a chime will sound and the “Tire Pressure
Monitoring Telltale Light” will flash on and off for
75 seconds and then remain on solid. Once you repair
or replace the original road tire, and reinstall it on the
vehicle in place of the spare tire, the TPMS will update
automatically and the “Tire Pressure Monitoring Tell-
tale Light” will turn OFF, as long as no tire pressure is
below the low-pressure warning limit in any of the
four active road tires. The vehicle may need to bedriven for up to 20 minutes above 15 mph (24 km/h)
in order for the TPMS to receive this information.
General Information
This device complies with part 15 of the FCC rules and
RSS 210 of Industry Canada. Operation is subject to the
following conditions:
•This device may not cause harmful interference.
•This device must accept any interference received,
including interference that may cause undesired
operation.
The tire pressure sensors are covered under one of the
following licenses:
United States ................... MRXC4N3MF9
Canada ...................... 2546A-C4N3MF95
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ADDING FUEL
Fuel Filler Cap (Gas Cap)
The gas cap is located on the driver’s side of the vehicle.
If the gas cap is lost or damaged, be sure the replacement
cap is the correct one for this vehicle.
CAUTION!
•Damage to the fuel system or emission control
system could result from using an improper fuel
cap (gas cap). A poorly fitting cap could let impu-
rities into the fuel system. Also, a poorly fitting
aftermarket cap can cause the “Malfunction Indi-
cator Light (MIL)” to illuminate, due to fuel vapors
escaping from the system.
•To avoid fuel spillage and overfilling, do not “top
off” the fuel tank after filling.
WARNING!
•Never have any smoking materials lit in or near
the vehicle when the gas cap is removed or the
tank is being filled.(Continued)
Fuel Filler Cap
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